Preheat the oven to 400 degrees. Line a baking sheet with a nonstick baking mat and set aside.

Combine the sugar, vanilla, and egg whites in a bowl and beat with a whisk for a few seconds until foaming. Add the flour, butter, almonds, and orange rind, mixing them in well. (The batter will be liquid.)

Drop about 1 1/2 tablespoons of batter for each cookie onto the prepared pan, leaving at least 4 inches between the mounds to allow for spreading. Bake for 10 to 12 minutes, until lightly browned.

Let the cookies “settle” for a couple of minutes and then, while they are still hot, lift them off the baking sheet and bend each cookie over a rolling pin or place it into a baguette mold so it takes on the shape of a curved roof tile. Allow them to cool long enough so they maintain their shape when removed. Let cool, and store in an airtight tin.